I am replace a toilet in my 1962 house. The seal (lead and oakum?) between the cast iron flange and the cast iron soil pipe was completely shot and when I lifted up the toilet, the flange came with it.

My current plan is to cut off a vertical section of the cast iron soil pipe and replace it with ABS attached with a fernco boot. This will let me attach a brand new ABS flange.

My questions:1. Is this my best course of action?2. What do you recommend to cut the cast iron? I've never worked with it and have heard that chain cutters can be tricky on older cast iron (is 40 years old considered older)?